A “duty cycle” is a term which in digital communication systems denotes the on/off ratio in an electrical signal. In particular, the duty cycle specifies the percentage with which a high level is present in a signal. The duty cycle is ideally 50% or 0.5.
The duty cycle represents an important criterion of dynamic interface signals in digital communication systems. Dynamic interface signals are, in particular, input and output signals of digital communication components. For the duty cycle, there are generally very restrictive specifications in order to ensure the function of individual components in an overall system. The higher the number of components, the more the specification has to be restricted. Complying with this specification under all boundary conditions such as temperature, supply voltage and manufacturing tolerances often constitutes a problem.
It is known, in the case of a large number of system components in a signal chain, to regularly incorporate a retiming stage (clock recovery) in order to regenerate the signal again with regard to its requirements. In this case, the signal is refreshed in particular with regard to jitter and duty cycle. However, such retiming stages disadvantageously require a considerable outlay on additional system components.